class AssetManager extends \Nette\Object
{
    /** @var array */
    protected static $stylesheets = array();

    public static function addCss($file)
    {
    list($filename, $path) = static::parseFile($file);

    if (!in_array($filename, static::$stylesheets)) {
        static::$stylesheets[$filename] = [
        'src' => $path . $filename,
        ];
    }
    }
    public static function getCss()
    {
    return static::$stylesheets;
    }

    private static function parseFile($file)
    {
    $explode = explode('/', $file);

    $path = preg_replace('/[^\/]+$/', '$1', $file) ? : NULL;
    $filename = end($explode);

    return array($filename, $path);
    }

}